


Ruby Scales

by etherealblades



Category: Kingdom Hearts
Genre: M/M, i didnt mean to make Vanitas come off as tsundere but i guess he kinda does, mermaid au, stubborn-as-hell Vanitas
Language: English
Status: Completed
Published: 2019-02-03
Updated: 2019-02-03
Packaged: 2019-10-21 10:47:45
Rating: Not Rated
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 3,927
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/17641325
Author URL: https://archiveofourown.org/users/etherealblades/pseuds/etherealblades
Summary: Vanitas is a mermaid-- sleek, elusive, and extremely violent. He kills humans for fun, for sport, to prove a point-- it doesn't matter. In his eyes, they're all scum. There is no way he'd ever let a filthy human lay their hands on him.That is, until he finds himself washed up on the beach one night, tangled up in a net.





	Ruby Scales

**Author's Note:**

> hi this is a repost, i took this down a while ago cuz i didnt like it, but i went back and touched it up and i like it again so hopefully it is here 2 stay lol
> 
> this isn't an extremely elaborate au BUT if ppl like it enough, i may just expand upon it! god knows i am thirsty for this kind of content
> 
> first off, this is young xehanort, not apprentice xehanort. the fucker in DDD who can stop time. that xehanort. you know the one
> 
> second, i based vanitas's mermaid design off of this mermaid tail right here: https://www.swimtails.com/wp-content/uploads/2018/04/crimson-siren-mermaid-tail-400x695.jpg (i don't have an actual drawing but you can interpret him as you like with the help of this pic)
> 
> thats it. hope u enjoy

Vanitas snarled loudly as he thrashed about in the ropes that constricted him. The net he was tangled up in was tight around his scales; some of his fins were caught in the square holes and were being tugged on painfully the more he squirmed around. He reached out with a clawed hand and tried to pull the net apart for what felt like the billionth time.

 

"Grrrhk--!"

 

No luck.

 

Vanitas fell slack and hit the sand with a thud, going still. His breath came out in ragged pants as his wild, golden eyes scanned the area. It was nighttime. The waves lapped quietly at the shore as the moon shone down on the earth, turning the sand pale. It was peaceful-- awfully ironic, considering his current situation.

 

The humans who set this trap had to be nearby. They were just waiting for when he was drained of his strength. When he would be vulnerable. And then they would kill him.

 

...But he couldn't see anybody.

 

He was furious, but more so at himself than anyone else (granted, there was no one else he could blame, but still.) He never fell for these traps! He was too clever and vicious for any human to catch. Vanitas couldn't count how many times he scared off curious humans, how many times he lunged out and sank his sharp teeth into their soft flesh. How many times he killed them to make a point.

 

And yet he fell for the simplest trap; the fisherman's net. This one seemed a lot stronger and sturdier than most nets, though. The rope was thicker and heavier than the ropes of regular nets, and it was complete with sturdy, metal weights to hold down whatever poor creature got tangled up in it. And Vanitas just so happened to be that poor creature.

 

Vanitas growled and twisted, trying to pull his tail out of the uncomfortable position it was currently in. The net had his tail and its fins caught in a way where moving made the net dig into his scales and tug on his fins. He was utterly hopeless. Even if he could find a way to break free from this net, he wasn't sure he would be able to swim correctly. He used up a lot of his strength trying to break free from the net. In his frenzy, he didn't consider anything else other than to break free and get the fuck out of here.

 

Now he was starting to regret his choices.

 

How did he get into this situation? Last thing he could remember was he was swimming towards the shore to check on humans...

 

He once thought it was redundant to check and see if there were humans in his territory at night, but he learned that some humans love to come out at night. This confused him, because he was fairly certain that humans were not nocturnal. But he became quite familiar with the sight of humans on the beach at night. Sometimes, they'd run around on the shore, splashing in the water and kicking up sand. Other times, he'd see them with small nets trying to catch the crabs scuttling around. The sight that confused him the most was when he'd see humans just sitting on the sand, staring up at the moon. He hated seeing them like that. They looked so calm, so peaceful. So docile.

 

It was a stark contrast to their true nature. The sight never failed to make Vanitas curl his lip in disgust.

 

Vanitas blinked, snapping out of his thoughts for a second. Right, he needed to get his shit together and figure out how to get out of here.

 

He huffed, taking in his surroundings. He was currently on his side, facing away from the water. He wasn't quite sure how far down the tide was by now, but he could hear the faint lapping of water against the shore. Trying to turn around on his other side would require him to twist against the net, and that would only apply more strain to his tail. He couldn't afford hurting his tail any more than it already was. So, he pushed that option out of his mind and tried to think more.

 

He had gotten distracted while swimming near the shore. There must have been a net in the waters, hidden out of view. How could he have missed that? If only he had been paying attention, he wouldn't have gotten caught in it. If only he had gotten his shit together, he wouldn't be so helplessly tangled up in it, and he could have--

 

Vanitas immediately tensed up upon hearing a sound. His yellow eyes frantically scanned the area, looking for the source of the noise. And then he saw it.

 

A human.

 

There was a human standing not too far from where he was. It appeared to be male. He was around six feet tall, and looked to be in his late teens, possibly early twenties. He had white hair that looked like snow from the way the moonlight shone on it, and it contrasted starkly against his dark skin. He had molten, golden eyes that were staring directly at Vanitas, taking in his entire form. He looked... curious. He shifted, and Vanitas suddenly noticed the bag that was hanging off of his shoulder from a strap. The human reached into his bag, glancing back up at Vanitas with fascination.

 

Vanitas growled and hissed, flashing his sharp canines at the human. This had to be the one who set the trap. How else would he have known that a mermaid was trapped on the shore? "You-- don't come near me!"

 

The human was still rummaging around in his bag as he stared at Vanitas. Then, he pulled out something, and walked closer, settling down on his knees. Vanitas recognized the glint of a knife in his hand and howled.

 

"I'll kill you! You disgusting creature! I'll rip the flesh right off of your bones--!" Vanitas attempted to lunge at the human, but he ended up slamming back against the sand, snarling in pain. His eyes were wide with fury and he panted heavily, not breaking eye contact with the white-haired man. "Get out of here. Leave me alone. I'll flay you alive. Don't come any closer."

 

The human didn't budge. It almost looked amused. Vanitas hissed and flashed sharp fangs at the stranger.

 

"I SAID--"

 

"Stop struggling."

 

Vanitas froze, momentarily stunned that the human talked back to him.

 

The human gestured to the net with his knife, then used his free hand to point at himself. "Relax. I understand your hostility, but I haven't come here to hurt you." He spoke calmly. "I'm Xehanort. I frequent this beach often in my own free time. I've heard rumors of mermaid sightings near here, but I thought it was all nonsense...” He shook his head. "I'm getting ahead of myself. I want to free you from that net, if you'll let me."

 

"I--" Vanitas huffed, his gills fanning out. "That's awfully sweet, coming from scum like you. I don't need your help. Get lost.”

 

"Not sure if I believe you." Xehanort hummed, his eyes trailing down to Vanitas's twisted tail. "You appear to be injured, and if I don't free you now, you could fall into the wrong hands. If you let me cut open this net, I'll let you go, no strings attached.”

 

"...I can kill you, you know." Vanitas narrowed his eyes. "I've killed countless of your kind, and I could kill you, too. I could rip out your throat and leave you here to bleed out onto this sand and die.”

 

"Then why haven't you done that already?"

 

"I-- I'm STUCK, you dumbass!"

 

He snorted and set his bag down beside him, clearly unfazed by the threats Vanitas was flinging at him. "Oh, yes, you sure are. So frightening. I suppose you're so frightening, I can't help you get out of that net, hm?"

 

Vanitas opened his mouth to retort, but closed it after a second. He could tell Xehanort was messing with him, but he desperately needed his help. Not that he would admit that. He was above asking for help, especially from the likes of a human. The day he asked a human for help was the day he grew legs and walked out of the ocean.

 

He simply growled in his throat and said nothing, staring back at the human with wary eyes. He allowed the tension to leave his body, feeling slight relief when the ropes ceased digging into his scales. Submission was foreign to Vanitas, but damn it, he had no other choice.

 

"There, that's it." Xehanort nodded. He reached out slowly to grab a portion of net that was near Vanitas's tail. He made sure to be slow with his movements; he didn't want to startle the mermaid any more than he already was. Xehanort wasn't convinced that he could do anything through this net, but being too careful couldn't hurt. "Just let me help you." He scooted closer to Vanitas, glancing back at the mermaid to make sure he wouldn't lash out at him again before hooking the tip of the knife under a portion of rope. “This may take a while, so... just bear with me.”

 

Thankfully, the mermaid had no retorts to this, as he simply fell slack and bore his bright, yellow eyes into Xehanort's skin as he sawed away at the rope. Xehanort bit the inside of his cheek to prevent the grin that was threatening to creep up onto his face. He wouldn't deny that he was capable of harming him, but here in this current position, he seemed... adorable, almost. In a weird, angry-mermaid way. He was quite the creature.

 

...The creature. Hm.

 

"Do you have a name?" He suddenly asked, curious if mermaids called themselves anything. It would certainly be better than constantly calling him "creature." Then again, maybe asking for names was taboo amongst mermaids, and maybe he would just piss off the already hostile sea creature. At this rate, Xehanort breathing was pissing the mermaid off.

 

The mermaid stared at him for a long moment before curling his lip at him and looking away. Xehanort sighed and looked back on the net he was trying to cut away, figuring it would take a bit of pushing to get straightforward answers from this thing.

 

But then he spoke up. "It's Vanitas."

 

Xehanort slowed in his sawing, turning to look at Vanitas. A smile spread across his face slowly. "...Vanitas. That's an interesting name."

 

Vanitas snorted. "Yours isn't the greatest, either."

 

"Believe me, I know." He chuckled, feeling a surge of confidence when he managed to cut through the rope. The moment was short-lived, however, because Vanitas suddenly thrashed and tried to tug at the small section Xehanort had cut away.

 

"Hey-!" Xehanort reached out and tried to push his hands away, and Vanitas snarled, sharp canines snapping near his fingers.

 

"LET ME GO!"

 

"I'm nowhere near done cutting this damn thing--!" Xehanort grabbed a handful of rope and yanked Vanitas back towards him. A bold move on his part, but it was more out of frustration than bravery. "You'll have to be patient if you want me to help you. Or else I won't be able to get you out, and whoever set this trap here will come for you at dawn." He let his words hang in the air for a moment as he watched Vanitas carefully. "Is that clear?"

 

The mermaid stared up at Xehanort with wild eyes, his chest rising and falling after his little lash-out. His jaw was clenched tight. Xehanort worried for a brief moment that he would fail in getting Vanitas out of this net. He was too stubborn. Too aggressive. At this rate, it would be dawn before he could get the mermaid out of here, and by then, the fishermen would arrive to check on the traps they had set.

 

The shifting under Xehanort snapped him out of his thoughts. Vanitas had fallen back down against the sand, letting out a low growl. No snarky remarks. No threats (well-- if you didn't count bitter growling as threats.) Vanitas fell silent and didn't budge when Xehanort slowly scooted forward and tugged on the net to resume his cutting. It seemed like he finally gave up fighting.

 

“I promise I will get you out of here. Just... please cooperate.”

 

“...Alright.”

 

Xehanort couldn't hide the grin that tugged at the corner of his mouth this time. He continued with the task at hand.

 

The only sound for a while was the sound of the gentle waves hitting the shore. Xehanort was busy cutting open the net, very aware of the pair of yellow eyes that bore into his skin.

 

But even Vanitas grew tired of keeping up the aggressive act, and he eventually started to really take in Xehanort's features. He noticed certain strands of his white hair fell forward in front of his face, and his hair was fairly long, going past his shoulders a bit. His ears also appeared to be pointed at the tips, which definitely did not seem normal, but Vanitas didn't know enough about humans to debate this topic in his head. His eyes trailed down further and he noticed the man wasn't wearing anything too extraordinary-- just a black tank top and some dark grey baggy shorts. Vanitas's lingering doubts of Xehanort being a fisherman were snuffed out with the realization that this man was probably (he put heavy emphasis on the word “probably”) just some ordinary human. His bag didn't even seem like it had much to offer, either-- just some pens, pencils, and a notebook peeking out at the top were all he could make out.

 

Xehanort noticed Vanitas eyeing him with wide, curious eyes (no anger or hostility in them-- he looked like a cat, in Xehanort's opinion), and he chuckled. "Something on your mind?"

 

Vanitas blinked and jolted slightly. Caught in the act.

 

“No.” Was all he said, curling his lip up and hoping his face wasn't as red as the tips of his scales right now.

 

Xehanort snorted, deciding not to press further, and pulled the portion of the net he cut away from Vanitas's tail, leaving part of it exposed. With part of the net gone, now he could really take in Vanitas's features. It looked like some of his scales were pulled off from him getting tangled in the net (no doubt his thrashing about contributed to that) and some of his fins had cuts in them, but the injuries didn't seem too serious. Xehanort's eyes trailed along the black-and-red tail, mesmerized. The way the moon shone on his scales... he seemed ethereal.

 

Xehanort was staring. He couldn't help it. Vanitas's tail was fascinating. The black scales tipped with a vibrant red, adorned with fins with curled tips that seemed to fan out slightly whenever Vanitas breathed. He was certain the scales would feel smooth, almost akin to that of a snake's body.

 

"Quit staring." Vanitas warned, sitting upright a little.

 

"Pardon me. Your scales are just... very pretty." He responded, pausing for a moment. Xehanort shook his head, not wanting to lose Vanitas's trust with blatant staring, and reached out to continue cutting away at the net. Vanitas tensed up and growled, but the growl was immediately cut off when the mermaid realized Xehanort wasn't trying to harm him.

 

Eventually, Xehanort was able to pull a massive part of the net away from Vanitas, giving him enough room to twist out of. Vanitas, surprisingly, shifted slowly and carefully pulled himself out of the net. Xehanort sat on the sand and watched him, getting a better look at his form now that he wasn't caught in a giant net. He couldn't deny that Vanitas had a sort of otherworldly beauty.

 

When Vanitas was free, Xehanort took the net and pushed it behind them, deciding he would dispose of it later. Disposing of it would at least give the fishermen the impression that maybe some creature managed to break out of the net, which was better than them finding out that he tore open their net to release a mermaid. That would only give them more incentive to keep placing traps here.

 

Vanitas hesitated for a moment after Xehanort kicked the net aside, looking down at his tail, then turning back to look at the man.

 

"I..." Vanitas's voice trailed off and huffed. "...Thank you."

 

"'Thank you?' You've finally learned some manners."

 

"Shut up." His gills flared out, Xehanort noticed. Maybe he does that when he's embarrassed.

 

Vanitas stared at him for a moment longer before speaking again. "...You're fascinated with my tail."

 

"I'm fascinated with all of you in general." Xehanort admitted. "Forgive me for not having seen a mermaid before. You don't usually see them walking in the streets."

 

Vanitas looked at his own tail, fanning his fins out and making sure nothing was seriously damaged. "Hm." He paused, observing his wounds. Broken and missing scales, cut fins, and a slight knot at the tip of his tail. Great. His entire body felt as if it was on fire. Vanitas shifted his body so he was sitting up and leaned forward, running his clawed hands along the small wounds on his tail.

 

Xehanort noticed him prodding at his wounds and spoke up. "Do you need help? I think I might have--"

 

A warning growl cut him off. "You want to touch me?”

 

"I kind of have to if you want me to help you. Unless if you want to apply the medicine yourself, I suppose."

 

"How do you know if any of your stupid human medicine will work on me?"

 

Xehanort shrugged. "I don't. But it's worth a shot, is it not?"

 

"You're stupid." Vanitas hissed.

 

"And here I thought you were starting to be nice."

 

Vanitas said nothing and picked at his scales, going silent for a bit. Then he shifted closer to Xehanort and pointed at his wounds. "Fix those." It wasn't a question.

 

Xehanort was both amused at Vanitas's inability to ask for help and shocked that Vanitas was allowing a 'disgusting human' to touch him. He tugged his bag closer to himself and rummaged through it, searching for anything that could help at least ease the pain. Notebook, pencils, pens, notes... Xehanort's eyes lit up when he pulled out some bandages. "Ah. Here, if I just wrap up these wounds, they should heal on their own. But don't take these off until you let him heal for a few days. Or else you might just make them hurt more, and they could get infected."

 

Vanitas frowned at the bandages, likely having never seen any before. The thought of Vanitas poking curiously at everyday human objects roused an amused snort out of Xehanort. He took the roll of bandages and leaned forward, reaching out with one hand carefully. He made sure to look at Vanitas before touching him to gauge his reaction. The mermaid's lip curled up slightly and he shifted under him, but there was no lashing out or threats of killing him. They were making progress.

 

Xehanort carefully wrapped up the small wounds Vanitas had, resting a hand on his tail when he was finished. Out of curiosity, he slowly dragged his hand down across, the scales, marveling at how smooth they were. Just like the body of a snake. He had great intuition.

 

Vanitas twitched, yet he did not pull away from him. "What are you doing." It came out more like a statement rather than a question.

 

"Nothing." Xehanort put away his bandages and looked back at Vanitas. "I'm just doubting your self-proclaimed hatred for humans, since you allowed me to free you and I even had the honor of touching you.”

 

"Shut up. You're the most annoying human I've ever met in my life."

 

“You've actually spoken with humans? I thought you simply killed them on sight.”

 

“Hnn.”

 

"Oh, relax. I'm just messing with you.” Xehanort hummed and stared at his tail, his grin slowly fading away. He couldn't deny that he was enamored with... everything about Vanitas. He was unlike anything he'd ever seen before. It was the kind of stuff fairy tales would talk about-- a beautiful mermaid with gleaming scales, but viciously sharp teeth. He wanted to observe him all day, but there was no way Vanitas would stick around that long. Besides, he needed to flee the scene before dawn, just in case those fishermen showed up.

 

A thought suddenly clicked in Xehanort's mind. He glanced back up at Vanitas. "Do you mind if... I take some notes? Of... of you?"

 

Vanitas didn't say anything for a long time. Xehanort almost took his lack of response as a definite "no," but then he felt a scaly tail flop onto his lap. He looked back at Vanitas, but the mermaid wasn't saying anything. Vanitas seemed much more interested in the sand all of a sudden.

 

Xehanort figured he'd miss his chance if he poked fun at him again, so he said nothing as he quickly pulled out his notebook and a pen. He jotted down notes on Vanitas's various fins, the color of his scales, how smooth they were to touch. And he even lightly dragged his hand across the mermaid's tail, touching a few of his fins in the process. Vanitas definitely tensed up and growled lowly occasionally, but surprisingly, he did not twist away and crawl back into the water. Even though that option was very open to him. The ocean wasn't going anywhere.

 

"Fascinating..." Xehanort murmured.

 

"Don't think you'll ever be able to do this again." Vanitas warned.

 

"That implies we'll be meeting again in the future." He looked up. "You'll come back to see me?"

 

"I never said that."

 

"I come here quite often, you know. I like to spend my free time here going over my research." Xehanort said. "You'll definitely see me if you live around here."

 

Vanitas curled his lip in disgust. "Whatever. Just stay away from me."

 

Xehanort couldn't resist poking at him. "You sound like you despise me, yet you let me touch you. Why?"

 

"Consider it repayment for freeing me. Nothing more." Vanitas's gills fanned out again. "Yet you're never getting any favors from me ever again. If I see you drowning, I'll just let you die."

 

"Such a charmer."

 

Vanitas pulled his tail off of Xehanort's lap. "Goodbye, Xehanort. If you tell any of your human friends about me, I'll kill all of them-- and you." He snarled, then crawled back into the water with surprising strength and speed. Xehanort stood up and watched Vanitas breech the water, noticing how sleek he looked in the water. He followed him into the water, stopping when the water hit his ankles.

 

"Vanitas, wait."

 

The mermaid stopped and turned around.

 

"Will I see you again?"

 

"...Maybe."

 

"So that's a yes." Xehanort smiled.

 

Vanitas glared at him and dived into the water, swimming away from him. Xehanort watched him swim out far, fascinated with the way his fins stuck out above the water. Vanitas was certainly a unique creature. His attitude was... something. But it amused him.

 

Xehanort began to turn away, when something caught his eye. He stopped and noticed a spiky head sticking out above the water. It stared at him for a moment, before diving back under the water for good.

 

Xehanort laughed to himself. He was full of surprises, that's for sure.


End file.
